Knee joint replacement procedures generally include preparation and resurfacing of the femur, tibia and/or patella. Briefly, the surgical procedure may involve calculated bone resections of each bone with the goal of replacing damaged articular cartilage, restoring the joint line and returning the patient to a pain-free movement of the knee joint.
In order to ensure proper knee joint kinematics, trial components of the femur, tibia and/or patella may be used intraoperatively. During the surgery, each bone is resected and the trial components are placed on each respective bone to allow the surgeon to trial the joint through a full range of motion. During trialing, the surgeon generally assesses the joint line, range of motion and ligament tension. Trial components generally represent various thicknesses, widths, or profiles to replicate the final implant prosthesis. The trialing process allows the surgeon to ensure proper knee joint function prior to the implantation of the final prosthesis.
Current methods of trialing and resecting the femur and tibia may leave the surgeon with little or no flexibility in modifying the final bone resections following trialing the implant components. For example, if the bones are resected according to a final plan, and during trialing the surgeon finds non-optimal joint kinematics, it may not be possible to make additional bone resections to optimize the kinematics. Rather, the surgeon may only be left with limited options, for example performing ligament releases, to attempt to optimize joint kinematics while remaining “stuck” with the bones resected according to the final plan. Further, the more components that are involved in trialing procedures generally translates to higher cost, greater complexity, and increased duration of the trialing procedure. There exists a need for new apparatus and methods to simplify the trialing procedure and to allow a surgeon to perform intraoperative dynamic trialing such that information gained during trialing may be applied to modify the final planned bone resections.